The application GB 2 147 204 A (applicant: J. H. Downey) discloses a hair comb that has a moisture sensor. This comb is designed to optically indicate the hair's level of dryness. It can therefore be used together with a hair dryer, for example. For example, a user can hold the comb in one hand and the hair dryer in the other hand and, based on the data display on the comb, direct the flow of warm air to parts of the hair that are still wet.
The patent application GB 2 432 310 A1 (Jemella Ltd.) discloses a flat iron having a temperature gauge and a switching circuit, which elements are designed to ensure that the flat iron can be switched on only after a certain minimum temperature has been reached. According to this disclosure, suitable minimum temperatures are between roughly 0° C. and 10° C. As the application describes, switching on the device at temperatures beneath a certain threshold can be disadvantageous, in particular because the flat iron can then be damaged by any condensation that is formed.
The European patent specification EP 0 176 003 B1 (Wella A G) discloses a method for measuring and regulating the amount of moisture in the hair that can be used with hair drying hoods. Hair drying hoods like the ones typically used in hair salons are generally equipped with a return air duct. A humidity sensor can then be installed in this return air duct. This sensor in turn is designed to generate a signal to switch off the drying program.
The European patent application EP 1 400 187 A1 (Cho) discloses a switching circuit by means of which the temperature of a flat iron can be kept constant. This exemplary switching circuit is, like many other switching circuits, designed to receive measurement data from a temperature sensor and, to the extent possible, to keep the flat iron at a constant, preset temperature. The temperature sensor is thus not used to vary the temperature but rather to keep the once-preset temperature constant.
Thus, the prior art has several disadvantages and limitations. In particular, despite various attempts at temperature regulation and process control, no way has been found to automatically and conveniently control the temperature.
The problem of the present invention is to provide a hair treatment device and a corresponding method by which hair properties can be measured and temperature control can be used in the hair treatment device.
This problem is solved by a hair treatment device according to claim 1 and a method for treating hair according to claim 11.